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ENCLOSURE 3

PUBLIC PARTICIPATION RECORD

As required by 40 CFR 51.102(e), the complete record of testimony is located at the 

Department of Environmental Quality. The department contact to access this 

information is the Director, Air Division.

As required by Section 2.1(h) of Appendix V of 40 CFR Part 51, below is a summary of 

the testimony received and responses thereto. Included is a brief statement of the 

subject, the identification of the commenter, the summary of the comment and the 

response (analysis and action taken). Each issue is discussed in light of all of the 

comments received that affect that issue. All comments have been reviewed and 

responses developed based on an evaluation of the issues raised in consideration of 

the overall goals and objectives of the air quality program and the intended purpose of 

the document under review.

1. SUBJECT: Sulfur dioxide (SO2) emissions.

COMMENTER: National Park Service

TEXT: DEQ has proposed addition of a caustic wet scrubber to control SO2 emissions 

from the rotary kiln. We agree and fully support this proposal.

RESPONSE: Support for the proposal is appreciated.

2. SUBJECT: Nitrogen oxide (NOX) emissions, cost effectiveness of selective catalytic 

reduction (SCR) control.

COMMENTER: National Park Service

TEXT: We agree that SCR in a high-dust location on this rotary lime kiln poses

problems that render this approach technically infeasible in this situation. There is a 

growing successful track record of SCR use in the United States that indicates that 

spent catalyst and ammonia use are not a significant risk if proper procedures are 

followed.

The following comments are directed to O-N Minerals' June 4, 2009 response to DEQ 

as it relates to the cost-effectiveness of a tail-end SCR system located downstream of 

the existing baghouse.

Except as noted elsewhere, we accept O-N's estimated costs at face value, and 

appreciate their effort to provide that information in such detail. We believe that O-N's 

operating cost for "Supplemental Natural Gas Firing" may be overstated. We recently 

received an analysis of tail-end SCR as it might be applied following a wet scrubber at 

Basin Electric Power Cooperative's (BEPC) Leland Olds Station Unit #2 in North
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Dakota. In that analysis, BEPC assumed that enough heat could be recovered that the 

additional natural gas heating requirement to operate SCR would be only 50°F. If we 

compare that Leland Olds estimate to the 200°F increase estimated by O-N, there is 

the potential to cut natural gas use by 75%.

We believe that O-N has underestimated the effectiveness of SCR at 80% control 

efficiency (305 tpy reduction). It is generally assumed that SCR can attain at least 90% 

control--which should be especially likely in a low-dust location. (The Leland Olds Unit 

#2 BART analysis assumed 90% control.) A 90% reduction at O-N could result in up to 

340 tpy removal. We entered data into a spreadsheet that adjusts the O-N Minerals 

results to account for reduced reheat cost and increased NOX removal. The resulting

$5,100 per ton cost-effectiveness is substantially lower than the $7,500 per ton 

estimated by O-N Minerals.

Unless a control technology option is determined to be technically infeasible, the full 

five-step BART process should be applied. In this case, tail-end SCR is technically

feasible and its costs are low enough to justify an analysis of the visibility improvements 

that would result from its application.

RESPONSE: The comments offered by the National Park Service (NPS) do not 

address--or change--our position as stated in our September 22, 2009 letter responding 

to NPS’s original comments (provided during NPS’ formal 60-day review period). As 

detailed in the letter, SCR has not been applied to or demonstrated on any kiln (cement 

or lime) in the United States. The limited data derived from one European cement kiln 

SCR application indicates poor performance (resulting in the SCR being replaced by 

SNCR at that location). We have found no use of SCR on a lime kiln anywhere. 

Accordingly, and as detailed in our 9/22/09 letter, we find that SCR is not a candidate 

for technology transfer for BART consideration.

Nonetheless, we offer the following responses to the points raised by NPS during the 

public comment period.

It is uncertain that it would be technically feasible to retrofit the existing rotary kiln setup 

at the Strasburg site to accommodate a heat exchanger for the purpose of heating the 

baghouse exhaust. Kiln heat is already recovered and used to heat limestone in the 

preheater, so it is unlikely that there would be enough residual heat to appreciably raise

the baghouse outlet stream temperature. It is not reasonable to conclude that O-N’s 

natural gas heating requirement would be 50°F (i.e., would be reduced by 75%) based 

on the requirements of a coal-fired boiler installation using heat recovery. 

As stated in our 9/22/09 letter, we believe 80% is an appropriate control efficiency basis 

for a novel application of SCR such as that on a lime kiln. There are data available 

from one application of SCR to a kiln (a cement kiln, not a lime kiln) in Europe; the data 

show that the SCR achieved an average control efficiency below 50%. We also note 

that several recent entries for applications of SCR on EPA’s RACT/BACT/LAER 
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Clearinghouse (RBLC) are listed at efficiencies below 90%, which reflects the processspecific nature of SCR effectiveness. As we previously concluded, although SCR is 

capable of achieving 90% reduction efficiency in certain applications, it would not be 

appropriate to apply that standard to an application of SCR to a lime kiln.

The adjusted cost per ton value ($5,100) presented by NPS is based on several 

assumptions. First, it presumes that a heat exchanger retrofit is technically feasible on 

the rotary kiln. Secondly, NPS’s revised calculation does not include an adjustment to 

capital costs to reflect the cost of the retrofit, if it is feasible. Finally, the revision is 

based on 90% control efficiency, which, as explained above, we find to be inappropriate 

in this case. We therefore do not find the adjusted cost per ton to be an accurate

indicator of SCR control cost in O-N’s case.

Modeling to assess the visibility improvement likely to result from application of SCR at 

O-N has not been conducted, because SCR was determined to be cost prohibitive. 

Additionally, as detailed above, SCR has not been applied to a lime kiln and we do not 

find it to be a candidate for technology transfer consideration under the BART 

guidelines. The analysis conducted to determine BART for O-N is fully consistent with 

the five-factor evaluative approach outlined in the BART guidelines (40 CFR Part 51, 

Appendix Y).

3. SUBJECT: Changes to permit conditions and SIP revisions.

COMMENTER: O-N Minerals (Chemstone) Company

TEXT: The proposed BART permit contains numerous and specific conditions that we 

understand will become part of Virginia's state implementation plan (SIP) once finalized 

and approved by the U.S. Environmental Protection Agency (EPA). Given that this 

facility in the near and long term may undergo permit changes that could result in future 

permit conditions that differ from those that incorporated in this permit, we have 

previously suggested to DEQ that this permit contain certain language to allow for 

permit modifications to minimize the possibility of having to modify the SIP to 

accommodate future permit requirements that may conflict with the BART permit as 

drafted. We appreciate that DEQ has considered this request previously and we 

understand some regulatory options may exist to reduce the opportunity for SIP 

revisions to be necessary. However, we remain concerned that future permitting efforts 

at the facility may require SIP revisions before they can be implemented without such 

permit revision provisions being incorporated in this permit. Accordingly, we appreciate 

DEQ reconsidering this aspect of the permit during this phase of the process.

RESPONSE: We understand O-N’s desire to simplify the administrative SIP revision 

process that may be required to address future modifications at the facility. 

Nonetheless, there is no way to avoid the need for a SIP revision if O-N wishes to 

change the terms of the BART permit in the future. We note that this is the case for 

any facility holding an air permit that is part of Virginia’s SIP. 
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4. SUBJECT: Scrubber installation date.

COMMENTER: O-N Minerals (Chemstone) Company

TEXT: We previously suggested that Condition 4 be revised to accommodate the 

timeframes that the company is working under relative to installation of an SO2

continuous emission monitoring system (CEMS) and, if necessary, the design, 

engineering, permitting and installation of add-on control equipment as applicable.

DEQ has not agreed to accept our proposed revision to this condition in prior 

discussions. We would prefer not to formally challenge the permit or delay the revision 

to the SIP. However, we cannot agree to the proposed language of Condition 4 which 

would require us to install a scrubber by September 10, 2010. We must have time to 

demonstrate that a scrubber is not necessary and obtain approval for the alternative 

control technology. If we cannot make that demonstration after a reasonable period 

(including the requirement to install a CEM for SO2), we will need adequate time to 

install the scrubber (assuming we continue to operate the kiln). We recommend that 

Condition 4 clearly state that we have until September 10, 2011 to seek approval of 

alternative control technology. Therefore, we propose the following revised Condition 4:

4. Emission Controls: Rotary Kiln - No later than September 10, 2010, sulfur 

dioxide (SO2) emissions from the rotary kiln (U5) shall be controlled to achieve 

the SO2 limits set forth in this permit. Unless the Director, Valley Regional 

Office, approves inherent process scrubbing as an alternative control technology 

by September 10, 2011, a wet scrubber shall be installed by September 10, 

2012. The wet scrubber or other technology employed to meet the SO2 emission 

limits shall be provided with adequate access for inspection and shall be in 

operation when the rotary kiln is operating.

(9VAC5-80-850, 9VAC5-40-7580, 9VAC5-40-7590, and 9VAC5-40-7650)

We also think it is important to state our understanding that the Director will agree that 

inherent process scrubbing is an approvable control technology if our SO2 emissions 

are consistently within the permit limits. We agreed to install a CEMS to provide data to 

demonstrate that inherent process scrubbing is effective and capable of meeting the 

BART permit without additional controls. Additionally, we understand that given the 

newness of continuous emission monitoring for SO2, occasional deviations of the SO2

limit should not preclude the Director from granting approval.

RESPONSE: We agree that an extension of the deadline to install a scrubber is

appropriate, provided that the emission limits determined to represent BART for SO2

from the rotary kiln (Condition 23) are met by September 10, 2010. Accordingly, we 

have changed Condition 4 to read:
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Emission Controls: Rotary Kiln – No later than September 10, 2010, sulfur 

dioxide (SO2) emissions from the rotary kiln (U5) shall be controlled to achieve the 

SO2 limits in Condition 23. Unless the Director, Valley Regional Office, approves 

inherent process scrubbing as an alternative control technology by September 10, 

2011, a wet scrubber shall be installed by August 1, 2012. The wet scrubber or 

other technology employed to meet the SO2 limits shall be provided with adequate 

access for inspection and shall be in operation when the rotary kiln is operating. 

(9 VAC 5-80-850, 9 VAC 5-40-7580, 9 VAC 5-40-7590 and 9 VAC 5-40-7650)

Note that the scrubber installation date has been changed to August 1, 2012 (instead of 

September 10, 2012 as proposed by O-N) to comply with Virginia’s BART regulation (9 

VAC 5-40-7590.4).

5. SUBJECT: Wet scrubber.

COMMENTER: O-N Minerals (Chemstone) Company

TEXT: We also believe a wet scrubber will be sufficient and ask to remove the 

reference to "caustic" in the appropriate conditions including, but not limited to, 

Conditions 4, 9, 14, and 26j.

RESPONSE: As requested, we have removed the word “caustic” from all references to 

the scrubber throughout the permit.

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